The background description provided here is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Internal combustion engines combust an air and fuel mixture within cylinders to drive pistons, which generates drive torque. Air flow into the engine is regulated via a throttle. More specifically, the throttle adjusts throttle area, which increases or decreases air flow into the engine. As the throttle area increases, the air flow into the engine increases. A fuel control system adjusts the rate that fuel is injected to provide a desired air/fuel mixture to the cylinders and/or to achieve a desired torque output. Increasing the amount of air and fuel provided to the cylinders increases the torque output of the engine.
As an engine combusts air and fuel to generate drive torque, the engine produces particulates that pass into an exhaust system of the engine along with other emissions. Particulates include soot or smoke made up of micrometer-sized particles. The amount of particulates released into the atmosphere may be reduced by including a particulate filter in the exhaust system of the engine. However, particulate filters are costly and increase exhaust back pressure.